Our solar system is made up of our star, the Sun, and everything gravitationally bound to it, including the planets Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune, as well as dwarf planets like Pluto, dozens of moons, and millions of asteroids, comets, and meteoroids. But have you heard about Haumea?
Our Solar System has an egg-shaped dwarf planet called Haumea, which has two moons and a high-speed rotation.
The Discovery of Haumea
A team led by Mike Brown from the Palomar Observatory discovered a tiny, Pluto-sized body in images taken the previous spring shortly after Christmas in 2004. Astronomers dubbed the rock Santa.
Around the same time, Brown’s team made their findings public, a team of astronomers from the Sierra Nevada Observatory led by José Luis Ortiz Moreno announced the discovery of the body in images taken in March of 2003.
The object, known initially as 2003 EL61, was classified as a Kuiper Belt Object (KBO) until the International Astronomical Union reclassified it as the solar system’s fifth dwarf planet, following Ceres, Pluto, Eris, and Makemake. However, updated estimates in 2017 cast doubt on the dwarf planet designation.
The object was renamed after the Hawaiian goddess of fertility and childbirth. Its two moons were named after the goddess’s daughters, Hi’iaka and Namaka, who were said to have been born from Haumea’s body. (Source: Space)
The Characteristics of Haumea
Haumea orbits the sun in 285 Earth years. It is only 34 times the Earth-Sun distance at its closest, while it is more than 51 times the distance at its farthest. These distances, combined with Haumea’s small size, would make determining its mass and density difficult for scientists. However, the first of two moons were discovered orbiting the body in 2005, allowing scientists to determine the mass of the bodies.
Haumea rotates on its axis once every four hours, making it the fastest-spinning large object in the solar system.
Haumea’s rapid spin prevents it from forming a spheroid, instead causing it to resemble a slightly flattened football spinning end over end as if kicked. Haumea has the longest axis of 1,430 miles or 2,300 kilometers and the shortest axis of 619 miles or 996 kilometers. According to 2017 estimates of its mass and shape, Haumea’s density is likely similar to Pluto, and its shape may be too elongated to qualify as a dwarf planet after all.
Because different materials stretch out differently, the rapid spin enabled scientists to calculate their density. As a result, scientists believe Haumea is almost entirely composed of rock.
However, observations of Haumea reveal a brightly gleaming surface. Scientists have determined that while most of Haumea’s interior is rocky, it is protected by a thin icy shell.
Haumea also appears to have a dark red spot on its surface containing more minerals and organic compounds than the surrounding ice. Astronomers also discovered a ring system around Haumea in 2017 when it passed in front of the star URAT1 533-182543 on January 21, 2017. The starlight also assisted astronomers in more precisely measuring Haumea’s longest axis, which was discovered to be roughly 17% larger than previous estimates. (Source: Space)
Image from Nasa